Details

It takes a strong team to pull a water tanker. This pair looks like they're up to the task.
Good brakes are also important when hauling this heavy of a load. Note the brake pad on the rear wheel, and the brake lever near the driver seat, seen more clearly in detail view 1.
This location appears to be the Park Blocks; we know it's somewhere in Portland. In 1912 most roads were still dirt and gravel, and the tanker may be being used to keep the dust down on a dry summer day.
-- This photo is restored and printed by Old Oregon. Original courtesy of City of Portland Archives.